Previously on the Smackdown
|The faces of Venus|
The discovery of the phases of Venus by a variety of telescopists in the early 1610s has put paid to the long, happy consensus science of the Ptolemaic model, which now languishes on the ash-heap of history. The Aristotelians are gleeful, since Ptolemaic astronomy was at serious odds with Aristotelian physics. (Much like today's quantum mechanics is at odds with relativity.) However, they should hold their gobs, since several bits of Aristotelian Physics have also come under telescopic doubt: the Moon has mountains, Jupiter has moons, the Sun gots freckles, and comets have most unhappy orbits.
None of this proves the Earth is mobile or that the Sun is at the center of the World. The stationary Earth remains unimpeached and her alleged dual motions are falsified in the Popperian sense by a) a lack of visible parallax among the fixed stars (which falsifies the Earth's revolution) and b) a lack of discernible Coriolis effects (which falsifies the Earth's rotation). There are other counterarguments, as well, which await the development of such concepts as inertia. TOF would discuss inertia, but it's hard to get started.
Meanwhile, Galileo has been suckered by the Pigeon League into dabbling in Scriptural interpretation, never a good idea for an amateur during a Protestant Revolution. He's been cleared of suspicion of heresy in a confidential investigation, but in the process Copernicanism has attracted the notice of the Authorities -- who are mostly lawyers and politicians. Galileo tried to re-interpret Scripture because of his commitment to Copernicanism-as-physically-real and -- much as people react to a mass shooting by concern over guns (rather than, say, lunatics) -- the Authorities react to this free-lance exegesis by a concern over heliocentrism.
A decree of the Index had removed Copernicus' book from circulation for a few years pending a couple of corrections to statements that seem to assert the physical reality of the model. Galileo has been cautioned not to hold or teach the theory other than as a mathematical model. However, the late Cardinal Bellarmino had written that if a demonstration could be shown, there would be little problem in clearing up the Scriptural issues. The Church has never insisted on strict literalism. But while the Church, holding that Truth is One, would have no problem reading a scripture non-literally if the literal reading could be certainly demonstrated false, they are not about to do so for the sake of a plausible mathematical hypothesis. Given the history of science, this would hold exegesis hostage to phlogiston, or any other scientific fashion.
So all Galileo needs to do now is present empirical evidence that the Earth has a dual motion. Piece of cake.
Or is it?